Before he was a wealthy businessman and the lieutenant governor of Texas, David Dewhurst was a member of the U.S. Air Force and the CIA.

For years, Dewhurst didn’t discuss that time in his life very often, preferring to stress his success in the private sector and as an elected official in Texas.

Yet in recent weeks, Dewhurst has repeatedly pointed to his stints in the military and the CIA to draw a contrast between himself and his opponent in a July 31 Republican primary runoff, former Texas Solicitor General Ted Cruz.

“Four times in my life, I have raised my right hand: when I joined the United States Air Force, when I went into the CIA and twice in state government,” Dewhurst said during Monday’s televised debate in Houston. “I took a solemn oath to defend the Constitution and U.S. law against all enemies both foreign and domestic.”

A day later, at a press conference with Gov. Rick Perry, he noted that service in the military was something he and Perry shared.

“I volunteered to go into the United States Air Force during the Vietnam War, just like Gov. Perry did,” Dewhurst said. “And after that, I volunteered again, and went into the CIA and I served abroad in harm’s way.”

Fresh out of college, Dewhurst enlisted in the Air Force in 1967 with the hope of emulating his father, a World War II air force pilot who flew 85 missions. His father died at the hands of a drunk driver when Dewhurst was 3 years old.

Dewhurst’s eyesight didn’t meet the Air Force’s minimum standards for pilots, so he was first assigned to Plattsburgh, N.Y., helping guarding B-52 bombers loaded with nuclear weapons, according to a 2002 Texas Monthly profile. He eventually became an intelligence officer with the rank of first lieutenant, according to military records.

In 1970, at the age of 26, Dewhurst left the Air Force and joined the CIA. He learned about the agency through a father of a college roommate who worked there, he told Austin’s KXAN-TV last year. He said the CIA firsttalked with him about joining the agency during that time.

Dewhurst worked at the U.S. embassy in La Paz, Bolivia, but has said that his work for the State Department there was a cover.

“I had a full-time embassy job,” he told Texas Monthly. “After hours and on weekends I was tasked by my [CIA] boss in Washington to keep in touch with certain groups and foreign embassies and opinion makers that Washington was interested in.”

The timing of his Bolivian stint provided fodder for critics when Dewhurst ran for land commissioner in 1998. Bolivia’s elected government was overthrown in a bloody coup in 1971, which the U.S. government was accused of helping arrange. Dewhurst has insisted he had nothing to do with the regime change.

“I left Bolivia in 1973,” he told the Austin Chronicle in 2001. “I have no informed opinion of President Banzer's [administration], other than that during the late 1970s, the U.S. State Department and international banking interests applauded Bolivia's strengthening economy. That apparent accomplishment has been clouded by numerous and repeated allegations of human rights violations."

In the 1998 race for land commissioner, state Rep. Richard Raymond, Dewhurst’s Democratic opponent, described him as a former “spy.” Dewhurst disputed that characterization at the time.

"Using official language," Dewhurst told the Washington Times, "your traditional CIA officer is a case officer and he talks to different sources. You might call them spies. Kind of like a reporter."

Dewhurst reportedly left the CIA in 1974. Twenty years later, Congress created a blue-ribbon committee to look into how to reform the country’s intelligence committees. Dewhurst, by then head of his own energy and investment firm in Houston, was appointed to the committee by Sen. Bob Dole, a Kansas Republican.

President George H.W. Bush, a former director of the CIA, recommended Dewhurst for the position in a letter to Dole.

"David, as you will see from the enclosed letter and resume, knows the CIA from the inside,” Bush wrote. “He is now a successful businessman.”

At a 1996 press conference on the release of the commission’s report, Dewhurst spoke about the importance of sending a message to the country’s intelligence agents that their work was still valued.

“More people died in Oklahoma City than died in Desert Storm,” Dewhurst said. “It’s a very dangerous world, and most Americans in this political season seem to be thinking in terms of family and jobs, but they wouldn’t be thinking in terms of family and jobs if our intelligence agencies weren’t working as hard as they are on a daily basis.”

Dewhurst expressed a similar sentiment at Monday’s debate, advocating for Texans to send to Washington “a strong senator who understands the military, who understands the intelligence business.”

Jay Root contributed to this report.

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